Intermittent Explosive Disorder (IED) is increasingly acknowledged as a common, potentially disabling psychiatric condition. Despite this, there are currently no empirically supported behavioral treatments for patients with IED. The purpose of the proposed study is to assess the short-term and long-term efficacy of a cognitive-behavioral treatment (CBT), previously found to be successful in treating dysfunctional anger, for treating IED. Secondary goals of the project are to (a) explore mechanisms involved in the successful treatment of IED, and (b) examine individual differences associated with treatment response. This request for a Patient-Oriented Mentored Scientist Award (K23) serves to cultivate the candidate's research acumen as it relates to randomized clinical trials, advanced biostatistical methodologies, and cognitive neuroscience. Ninety subjects meeting criteria for both current research and current DSM IED criteria will be randomly assigned to either 12 weeks of CBT or 12 weeks of a supportive psychotherapy control condition. Subjects will be assessed before and after therapy as well as at 6 month and 12 month follow-up. Primary outcome measures will assess aggressive behavior, anger, and the presence of an IED diagnosis at post-treatment, 6-month follow-up and 12-month follow-up. Social and emotional information processing will be evaluated as potential mechanism of change. Trait aggression will be assessed as a potential moderating variable. [unreadable] [unreadable] [unreadable]